Dysfunction of early sensory stages of the Magnocellular visual and auditory pathways

Dysfunctional visuospatial attentional system

Disorder of the motor system including altered cerebellar physiology

Other structural MR studies have shown inconsistent results: for example, the observation of Galaburda has been replicated only in 50% of the MRI studies. Anatomical measures of other structures such as the Corpus Callosum have also provided variable results:

A recent VBM study, observed significant reductions of grey matter volume in areas of the brain associated with language and reading processing in people with a family history of dyslexia. Significant reductions were located bilaterally in:

Planum temporale

Inferior temporal cortex

Cerebellar nuclei

Left superior and inferior temporal regions

Finally, there is one MRI morphometric study on the cerebellum, found that, although normal controls had a larger right hemispheric cerebellar cortical surface, the cerebellar hemispheres in the dyslexic subjects were symmetric.

Conclusion: The coexistence of local cortical changes together with
abnormality of cortico-cortical connectivity within the language neural
network offers a realistic description of the neurology of dyslexia at
a systems level and explains why tasks like reading or naming, which
require the integration of multiple visual, phonological and
articulatory codes, are sensitive in revealing a dyslexic brain.

The
purpose of this site is to present questions and new ideas about
the above subjects.